UPDATE: 3/3/2017: One source added to bottom of list
UPDATE: 1/30/2017: Five(!) Sources added to bottom of list. I have no experience with any of them. As always, caveat emptor.
UPDATE: 11/16/2016: Two sources, both Facebook Groups, added to bottom of list. One dead link removed.
UPDATE: 9/13/2014: Finally did a long overdue cleanup of the list. Eliminated dead pages and sites that no longer appear to sell used brass instruments on-line, as well as updating links that have changed.
UPDATE: 12/18/2013: One source added to bottom of list
UPDATE: 11/2/2013: Two sources added to bottom of list
UPDATE: 6/20/2013: Two sources added to bottom of list
UPDATE: 1/7/2013: One source added to bottom of list
UPDATE: 12/21/2012 One source added to bottom of list
UPDATE: One source added to bottom of list 8/16/2012
UPDATE: 11/11/11: Added one source to the bottom of the list.
UPDATE: 10/2/11: I've added four sources to the bottom, removed a couple and cleaned up a couple of existing links.
UPDATE: 8/31/10 Added one source to bottom (Thanks Bill Dishman)
UPDATE: 7/3/10 Added one source to bottom of list
UPDATE: 5/16/10 Added one source to bottom of list
UPDATE: List updated 4/10/10 (one source added, one source removed)
UPDATE: 2/23/10 (one source added to bottom of list)
UPDATE: Updated 2/15/10 (one source added to bottom of list)
UPDATE: Updated 2/14/10 (one source added to bottom of list)
UPDATE: List updated 1/20/10 (one source added - thanks bobd0)
UPDATE: List updated 12/6/09 (two sources added to bottom of list)
UPDATE: List updated 12/3/09 (two sources added to bottom of list)
UPDATE: This list has been updated: 12/2/09

I put together this list of on-line sources for used trumpets and related equipment when the TH Marketplace went down in January of '09.

After TH and eBay - my two fave sites to browse for used equipment - this list is in no particular order. Nor am I promoting any of the businesses on this list. I've never dealt with the vast majority of them. Feel free to add to this list. Happy shopping.

Feel free to add to this list. Perhaps ultimately it could be better organized and made into a 'sticky' so that it would be easily accessible to all.

Yeah... I see many of your list also coincide with a lot of places I've looked to regarding repairs/mods. Three categories that come to mind for me are: 1) horns for sale, 2) repair shops, and 3) parts supplies. Maybe other folks have some other category ideas. It would be nice to have an exhaustive (and updatable) list such as what you've started. Nice job!

...I did not see this one so I'd add
http://brassandwoodwind.ca/trumpets.html
to the list...has a large collection of Strads right now._________________Randy Nelson
Olds Super Recording
Kanstul Chicago
Kanstul French Besson Marvin Stamm
Lawler C7
Getzen Custom 3051 LB RL

Thanks for the kind words. I'm glad some folks are finding this useful.

SupportLiveJazz, I'm so proud and humbled to have been singled out for this honor. I await the details regarding the awards ceremony and after-party.

I agree that it could be more refined with categories, comments, etc. Also, while the list I supplied is limited to USA sources, other qualified folks could create lists of on-line sources in other countries. That would be cool.

Randall Nelson, thanks for adding brassandwoodwind.ca. I remember seeing that in my web surfing, but I forgot to bookmark it.

Blackbird, I have no experience with thetrumpetshop.com, but if memory serves, the owner (or perhaps manager) of the shop has posted here on TH and recently wrote that the website is new. You may want to try searching the TH Forum for thetrumpetshop.com and see what comes up.

Thanks Rich - I like the sax website (junkdude) because they have reasonable prices on their horns. Other websites seem determined to drive up the price of certain used trumpet models.

I agree, Daniel. They're nice people to deal with, also. Anytime I have emailed them with questions on particular horns they were very quick and cordial with a response. They update their listing fairly regularly, too.

Thanks to all for the advice and additions. As suggested, I have indeed updated my original post to include the sites added by others. If more sites are added in the future I will update the original post accordingly.